Members of a group studying the future of menhaden learned a lot about the small, oily fish on Thursday but left their first meeting with one nagging question: how many are in the Chesapeake Bay?

The panel of legislators, environmentalists, marine industry officials and recreational fishing interests heard from federal and state biologists on the fish, but little information was specific to the bay. Atlantic menhaden are found along the East Coast, from Maine to Florida, but the bay attracts many of the fish.

"We need science that's specific to the Chesapeake Bay and not the entire Atlantic stock," said Sen. Ralph Northam, a Norfolk Democrat and co-chair of the committee.

The group is looking at shifting oversight of the menhaden fishery from the General Assembly to the Virginia Marine Resources Commission, which has had success restoring the bay's blue crab population.

The creation of the 26-member study panel follows a report earlier this year by the Atlantic States Marine Fisheries Commission. While the commission said menhaden is not overfished, it sounded some alarm about the stocks of young fish.

Omega Protein Corp., which employs about 300 people during the May-to-December fishery, is allowed to catch 109,020 metric tons of menhaden annually from the Virginia portion of the bay. The catch is processed at its Reedville plant into meal used for animal and pet food and into omega-3 fish oils sold as heart-healthy food supplements.

The Omega fishing fleet has made the Northern Neck town one of the biggest fishing ports in the U.S., based on total weight of the catch.

Omega, which was invited to sit on the panel, declined to participate.

A spokesman for Omega said the company was concerned that science would be pushed aside by members who have "preconceived notions about this fishery and the health of menhaden."

"We just didn't think it was going to lead to fruitful discussions," Omega's Ben Landry said in an interview before the meeting.

Only about half the study group attended. Labor and watermen's groups did not attend, nor did the NAACP. Many of Omega's fishermen are African-American.

Much of the science discussed Thursday played down the value of menhaden as a filter fish for the bay and concerns that Omega boats scoop up forage fish key to valued game fish such as stripers and blue fish.

"If there's one certainty about menhaden science it's that both sides cherry-pick their data," said Jack Travelstead, deputy commissioner of the Virginia Marine Resource Commission.

He estimated the cost of monitoring menhaden would be $500,000 annually.

Still, members of the study group said they wanted more data.

"We want to have more answers," said Lisa M. Guthrie of the Virginia League of Conservation Voters and a member of the study group. "I think everybody wanted to have more cut-and-dried answers on whether it is being overfished or whether it isn't."

David L. Nobles of the Coastal Conservation Association said his group is convinced menhaden stocks have declined, though he has no science to support his observation.

"We used to see them all over the bay," he said. "We don't see them anymore."

Northam acknowledged that the menhaden fishing fleet — about 10 160-foot boats fish the bay and coast — are disconcerting to some of his constituents.

"They see these boats out there taking the menhaden and it's like, 'How can this be good?'"

He said the study group is committed to finding answers.

"As long as we're tasked with managing the menhaden fishery, as a legislator and an advocate for a healthy Chesapeake Bay I want to do it the right way," he said.